1. Field of the Invention
The present invention relates generally to a fluid pressure failure warning system for vehicle brakes, and more particularly to a brake pressure difference warning system used within a split type brake assembly and associated with a proportioning valve assembly for automobiles for cooperation therewith.
2. Description of the Prior Art:
Within a split or dual type brake system, at least two independent brake lines are provided so as to apply the brakes, and usually the front and rear wheel brakes are applied independently of each other. When a hydraulic failure occurs within one of the brake lines, the vehicle driver should be notified of the same, and many warning systems have been proposed in order to give such notice of fluid pressure failure to the driver.
It is also a conventional practice to incorporate a proportioning valve within the rear wheel brake line so as to thereby apply the proportioning brake pressure to the rear wheel brakes. The proportioning valve may sometimes be ineffective, such as for example, the reciprocable piston of the proportioning valve may be maintained seated upon a valve seat thereof so that no brake pressure is able to be supplied to the rear wheel brakes.
Under such conditions, it is desirable to give notice of such failure of the proportioning valve to the driver, and in addition, it is desirable to compensate the pressure decrease of the rear wheel brakes which is caused as a result of the interruption of fluid supply to the rear wheel brakes because of the continuous seating of the reciprocable piston relative to or upon its valve seat.